Isolierung und Charakterisierung einer Acetylester-Hydrolase aus Aspergillus rtiger / Isolation and Characterization of an Acetylester-Hydrolase from Aspergillus niger

1980 ◽  
Vol 35 (9-10) ◽  
pp. 696-698 ◽  
Author(s):  
B. Schöbel ◽  
W. Pollmann
Keyword(s):  
Molecular Weight ◽  
Acetic Acid ◽  
Temperature Optimum ◽  
Isolation And Characterization ◽  
Glyceryl Triacetate ◽  
Characteristic Features ◽  
The Stability ◽  
Acetic Acid Esters ◽  
Acid Esters

Abstract The characteristic features of an acetic acid esters hydrolyzing enzyme (acetylesterase, EC 3.1.1.16) are described. The pH- and temperature optimum were 7.0 and 40 °C respectively. The stability of the enzyme regarding different pH- and temperature conditions was investigated. The molecular weight of the acetylesterase could be determined to 160000. A small acetic ester hydrolyzing activity was found too with a molecular weight of about 25000. The activity was not inhibited by addition of di-isopropylphosphorofluoridate (DFP) or physostigmine. The KM-value for glyceryl triacetate was about 90 mM. Concentration of the enzyme was done by ultrafiltration and column-chromatography. The enzymatic activity tests were performed titrimetrically using glyceryl triacetate for substrate.

Synthesis and characterization of organic conductors derived from (1H-pyrrol-3-yl)acetic acid esters

1996 ◽  
Vol 6 (7) ◽  
pp. 1107
Author(s):  
Anh Ho-Hoang ◽  
Emmanuelle Schulz ◽  
Fabienne Fache ◽  
Giselle Boiteux ◽  
Marc Lemaire
Keyword(s):  
Acetic Acid ◽  
Organic Conductors ◽  
Synthesis And Characterization ◽  
Acetic Acid Esters ◽  
Acid Esters

scholarly journals The Blocked Amino-Terminal Peptide of Feather Keratin

1971 ◽  
Vol 24 (1) ◽  
pp. 179 ◽  
Author(s):  
IJ O'donnell
Keyword(s):  
Molecular Weight ◽  
Acetic Acid ◽  
Amino Groups ◽  
Amino Terminal ◽  
Acetyl Content ◽  
Electrophoretic Patterns ◽  
Isolation And Characterization ◽  
Primary Amino

Proteins extracted from reduced and carboxymethylated feather keratins (SCM-keratins) have been studied by Harrap and Woods (1964a, 1964b, 1967). They have demonstrated the presence of electrophoretic heterogeneity amongst the proteins and have obtained a molecular weight of approximately 11,000 in agreement with earlier work of Woodin (1954). There was no indication of marked heterogeneity with respect to size. Using acid hydrolysis and determination of acetic acid produced they found an acetyl content of 1 �30 molesj104 g in the rachis off owl feathers. These were thought to be attached to primary amino groups since there were no O-acetyl groups. In the present paper the isolation and characterization of the predominant, and probably sole, amino-terminal tripeptide from goose feather calamus is described. Goose feather calamus was chosen because its extracted proteins had one of the simplest electrophoretic patterns of proteins from the feathers of a number of species (Harrap and Woods 1967).

Isolation and Characterization of Plasminogen Activator from Pig Leucocytes

1974 ◽  
Vol 31 (01) ◽  
pp. 072-085 ◽  
Author(s):  
M Kopitar ◽  
M Stegnar ◽  
B Accetto ◽  
D Lebez
Keyword(s):  
Molecular Weight ◽  
Plasminogen Activator ◽  
Gel Electrophoresis ◽  
Gel Filtration ◽  
Ph Optimum ◽  
Isolation And Characterization ◽  
Ph Range ◽  
Inhibition Studies ◽  
Final Purification

SummaryPlasminogen activator was isolated from disrupted pig leucocytes by the aid of DEAE chromatography, gel filtration on Sephadex G-100 and final purification on CM cellulose, or by preparative gel electrophoresis.Isolated plasminogen activator corresponds No. 3 band of the starting sample of leucocyte cells (that is composed from 10 gel electrophoretic bands).pH optimum was found to be in pH range 8.0–8.5 and the highest pH stability is between pH range 5.0–8.0.Inhibition studies of isolated plasminogen activator were performed with EACA, AMCHA, PAMBA and Trasylol, using Anson and Astrup method. By Astrup method 100% inhibition was found with EACA and Trasylol and 30% with AMCHA. PAMBA gave 60% inhibition already at concentration 10–3 M/ml. Molecular weight of plasminogen activator was determined by gel filtration on Sephadex G-100. The value obtained from 4 different samples was found to be 28000–30500.

Preparation and Characterization of the High Molecular Weight [3H]Hyaluronic Acid

1992 ◽  
Vol 57 (10) ◽  
pp. 2151-2156 ◽  
Author(s):  
Peter Chabreček ◽  
Ladislav Šoltés ◽  
Hynek Hradec ◽  
Jiří Filip ◽  
Eduard Orviský
Keyword(s):  
Molecular Weight ◽  
Hyaluronic Acid ◽  
High Molecular Weight ◽  
Methyl Bromide ◽  
High Performance ◽  
Hydrogen Atoms ◽  
Isolation And Characterization ◽  
Labelling Procedure ◽  
Enzymatic Depolymerization

Two methods for the preparation of high molecular weight [3H]hyaluronic acid were investigated. In the first one, hydrogen atoms in the molecule were replaced by tritium. This isotopic substitution was performed in aqueous solution using Pd/CaCO3 as the catalyst. In the second method, the high molecular weight hyaluronic acid was alkylated with [3H]methyl bromide in liquid ammonia at a temperature of -33.5 °C. High-performance gel permeation chromatographic separation method was used for the isolation and characterization of the high molecular weight [3H]hyaluronic acid. Molecular weight parameters for the labelled biopolymers were Mw = 128 kDa, Mw/Mn = 1.88 (first method) and Mw = 268 kDa, Mw/Mn = 1.55 (second method). The high molecular weight [3H]hyaluronic acid having Mw = 268 kDa was degraded further by specific hyaluronidase. Products of the enzymatic depolymerization were observed to be identical for both, labelled and cold biopolymer. This finding indicates that the described labelling procedure using [3H]methyl bromide does not induce any major structural rearrangements in the molecule.

scholarly journals Tautomerisation in 1-(4-Methylphenylazo)naphthalen-2-ol and 2-(4-Methylphenylazo)-4-methylphenol: A Crystallographic and 13C{1H}NMR Study

1999 ◽  
Vol 23 (3) ◽  
pp. 178-179
Author(s):  
Wendy I. Cross ◽  
Kevin R. Flower ◽  
Robin G. Pritchard
Keyword(s):  
Acetic Acid ◽  
Nmr Spectroscopy ◽  
Resonant Frequency ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Nmr Study ◽  
Acetic Acid Esters ◽  
Acid Esters ◽  
Equivalent Carbon

The acetic acid esters of 1-(4-methylphenylazo)naphthalen-2-ol 1 and 2-(4-methylphenylazo)-4-methylphenol 3 are prepared and characterised by single crystal X-ray diffraction studies and 13C{1H}NMR spectroscopy; the position of the C(2)13C resonance for the ester is used to predict the position of resonant frequency of the equivalent carbon in the parent alcohols and hence, calculate the position of the azo-hydrazone equilibrium in these compounds.

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